JPS596919B2 - Roll plating method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to electroplating of continuous strip-shaped parts, strips, plates, etc., mainly of noble metals.

When applying electroplating to a strip-shaped part, especially when applying it only to one side, a spray nozzle is used and a liquid stream is used.

In particular, when performing electroplating of precious metals, it is necessary to precisely control the conditions of the amount of liquid to be sprayed because it is necessary to limit the electroplating to a localized area. When particularly strict conditions are required, masking tape is used to shield the current, but the cost of attaching and removing the masking tape increases. Furthermore, when press processing is applied to a band-shaped part, the jetted liquid flow also reaches the back surface, making it often impossible to plate only one side.In the case of precious metal plating, J~30% of the surface area is plated on the back side. A layer is formed and this results in loss.
The present invention relates to a plating method for plating opposing surfaces of objects to be plated using a rotating body. That is, it is characterized by continuous plating by utilizing the current current in the region formed by the plating solution carried up to the surface of the rotating body and the wet tension of the object to be plated, which runs continuously or intermittently. The roll plating method realizes highly efficient plating.
Hereinafter, specific examples of the present invention will be explained in detail.

The same reference numerals in the figures below indicate the same thing. FIG. 1 is a projection view showing the principle of the roll plating method according to the present invention.

Gold plating is required on the bent portion 1a of the band-shaped component 1 used for the connector. The strip 1 is kept exactly horizontal and fed in the direction of arrow A. A rotating body 3 immersed in a plating liquid tank 2 is provided parallel to this strip-shaped part 1, and the rotating body 3 is indicated by the arrow B.
Rotates by gaining power in a direction. A slight gap is provided between the top portion 3a of the rotating body 3 and the bent portion 1a of the band-shaped component 1 in parallel. Since the rotating body 3 rotates at high speed in the plating liquid, its surface becomes wet, and this liquid also comes into contact with the bent portion 1a of the band-shaped part 1, and the plating liquid is maintained in this gap due to the capillary action of the plating liquid. An anode 4 is provided in the plating bath, and a cathode potential is applied to the strip-shaped component 1, so that a current is applied through the plating liquid attached by capillary action. The strip 1 continues to move parallel to the rotary axis of the rotating body, while the rotating body 3
rotates continuously and adsorbs the plating liquid in the plating liquid tank.
The contact portion of the bent portion 1a of the band-shaped component 1 is replenished. For this purpose, the strip-shaped part 1 is partially plated in the form of a strip while running on the upper part of the rotating body 3. The plating liquid is continuously circulated by a pump between the plating liquid tank 2 and a storage tank (not shown), and filtration and heating liquid conditions are continuously adjusted. FIG. 2 is a schematic perspective view of main parts showing the structure of an embodiment of the roll plating method according to the present invention.

For the convenience of explanation, the plating liquid tank support structure has been omitted, and a portion of the continuous band-shaped component has been cut and removed as appropriate for the convenience of explanation. The band-shaped part 1 is pressed against the guide surface 5a of the guide part 5 by a large number of floating press rollers 6, and is fed horizontally while being kept at a constant height. A cathode potential is applied to the strip component 1 by a metal fixed brush 7. The rotating body 3 is held accurately horizontally in the plating liquid by shafts 3b at both ends, and rotates smoothly in the plating liquid by receiving power from the shafts 3b. The anode 4 is fixedly held in the plating solution in the vicinity of the rotating body 3. In the example, the length of the rotating body 3 is about 50 cm,
The rotation speed is 300 revolutions per minute. FIG. 3 is a cross-sectional view of a plating device for the roll plating method, in which the strip-shaped component 1 runs in a direction perpendicular to the plane of the paper.

The rotating body 3 is made of hard vinyl chloride and has a smooth surface. When the rotary body 3 rotates at high speed in the plating liquid, the surface of the rotary body gets wet, and further rotational force is obtained, and the plating liquid is carried to the top part 3a of the rotary body and enters the minute gap in the bent part 1a of the strip-shaped part 1. Wetting tension acts and the plating liquid fills the area. The surface treatment, material, etc. of the rotating body 3 are determined by the plating liquid composition,
It is selected depending on the heating conditions, plating metal, etc. FIG. 4 is a cross-sectional view of a plating device according to the roll plating method according to the present invention when the object to be plated is a flat strip, and the plating liquid comes into contact with the strip due to capillary action as in the connector embodiment of FIG. 3. A part of the material part 1 is plated.

FIG. 5 is a perspective view showing the principle of roll plating according to the present invention when double rows are arranged diagonally with respect to a strip.

By arranging the rotating body 3' obliquely with respect to the strip 1/, the contact area of the plating liquid (indicated by the two-dot chain line) between the strip 1' and the rotating body 3' is provided obliquely as shown in 3'a. I can do it. When the strip material 1' is run in the direction of arrow A, the plating width can be increased in accordance with the angle of the rotating body 3', and it is possible to proceed further and apply plating to the entire lower surface of the strip material. Further, by arranging the rotating bodies in parallel and obliquely in double rows, it is possible to increase the plating thickness or perform multilayer plating. As described above, according to the present invention, it is possible to plate both a strip material and a processed strip-shaped part by controlling the plating width to a constant width on one side or to the entire surface. This results in a significant reduction in precious metals, particularly gold, which can be concentrated in the most functionally important areas, making it possible to achieve both economic efficiency and improved functionality. When using partial functional plating made of precious metals such as platinum, palladium, and rhodium, as well as rare metals and other base metals in addition to gold and silver, a multi-layered and multi-row structure can be freely realized. Moreover, the band-shaped part is not limited to metal, and even if it is made of plastic film or the like, it is possible to economically attach a metal thin film by subjecting it to conductive treatment. Since the amount of rotation of plating liquid, especially expensive plating chemicals for precious metals, can be kept to a minimum, production asset management and quality control can be easily maintained. Furthermore, by limiting the plating area, the cleaning process is simplified, resulting in loss of chemicals, reduction in cleaning water, and simplification of waste liquid treatment. In addition, the plating device is short and compact, making it more economical, requiring a smaller installation area, and becoming lighter. This advantage makes it possible to combine other processes, and by incorporating the plating process according to the present invention into an automatic manufacturing process, the entire manufacturing series can be rationalized. As described above, the present invention not only streamlines industrial production, but also contributes to the economy by saving precious metals, and also contributes to social effects.

[Brief explanation of the drawing]

Fig. 1 is a projected view showing the principle of the roll plating method according to the present invention, Fig. 2 is a perspective view showing the structure of the roll plating method according to the present invention, Fig. 3 is a sectional view of the plating device of the roll plating method, and Fig. 4 FIG. 5 is a cross-sectional view of a plating device of the roll plating method according to the present invention for strip material, and FIG. 5 is a perspective view showing the principle when rotating bodies are arranged diagonally in double rows according to the roll plating method according to the present invention. In the figure, 1 is a strip-shaped component, 2 is a plating liquid tank, 3 is a rotating body, and 4 is an anode.

Claims (1)

[Claims] 1. Part of a cylindrical object made of a hard material is immersed in a plating solution and rotated to form a plating film on the surface, and then the object to be plated is run on the surface of the rotating cylindrical object to continuously A roll plating method characterized by plating the desired area. 2. The roll plating method according to claim 1, wherein the axis of the rotating body and the axis of the object to be plated, which travels continuously or intermittently, are parallel to each other, and partial plating is performed continuously. 3. In claim 1, the axis of the rotating body and the axis of the object to be plated, which run continuously or intermittently, intersect obliquely in parallel planes containing the axis, and the object to be plated is A roll plating method characterized by continuous plating on one side or the entire surface. 4. The roll plating method according to claim 1, characterized in that a plurality of the rotating bodies are arranged in parallel.